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Title: Collective dynamics of soft active particles

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Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review E
Additional Journal Information:
Journal Volume: 91; Journal Issue: 3; Journal ID: ISSN 1539-3755
American Physical Society
Country of Publication:
United States

Citation Formats

van Drongelen, Ruben, Pal, Anshuman, Goodrich, Carl P., and Idema, Timon. Collective dynamics of soft active particles. United States: N. p., 2015. Web. doi:10.1103/PhysRevE.91.032706.
van Drongelen, Ruben, Pal, Anshuman, Goodrich, Carl P., & Idema, Timon. Collective dynamics of soft active particles. United States. doi:10.1103/PhysRevE.91.032706.
van Drongelen, Ruben, Pal, Anshuman, Goodrich, Carl P., and Idema, Timon. 2015. "Collective dynamics of soft active particles". United States. doi:10.1103/PhysRevE.91.032706.
title = {Collective dynamics of soft active particles},
author = {van Drongelen, Ruben and Pal, Anshuman and Goodrich, Carl P. and Idema, Timon},
abstractNote = {},
doi = {10.1103/PhysRevE.91.032706},
journal = {Physical Review E},
number = 3,
volume = 91,
place = {United States},
year = 2015,
month = 3

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevE.91.032706

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Cited by: 8works
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  • Within the framework of semiclassical approximation a general formalism for deriving an effective current generating bremsstrahlung of arbitrary number of soft gluons (longitudinal or transverse ones) in scattering of higher-energy parton off thermal parton in hot quark-gluon plasma with subsequent extension to two and more scatterers is obtained. For the case of static color centers, an expression for energy loss induced by usual bremsstrahlung of lowest-order with allowance for an effective temperature-induced gluon mass and finite mass of the projectile (heavy quark) is derived. The detailed analysis of contribution to radiation energy loss associated with existence of effective three-gluon vertexmore » induced by hot QCD medium is performed. It is shown that in general, the bremsstrahlung associated with this vertex has no sharp direction (as in the case of usual bremsstrahlung) and therefore here, we can expect an absence of suppression effect due to multiple scattering. For the case of two-color static scattering centers it was shown that the problem of calculation of bremsstrahlung induced by four-gluon hard thermal loop (HTL) vertex correction can be reduced to the problem of the calculation of bremsstrahlung induced by three-gluon HTL correction. It was shown that for limiting value of soft gluon occupation number N {sub k} {approx} 1/{alpha} {sub s} all higher processes of bremsstrahlung of arbitrary number of soft gluons become of the same order in coupling, and the problem of resummation of all relevant contributions to radiation energy loss of fast parton, arises. An explicit expression for matrix element of two soft gluon bremsstrahlung in small angles approximation is obtained.« less
  • The generalized density matrix method is used to calculate microscopically the parameters of the collective Hamiltonian. Higher-order anharmonicities are obtained consistently with the lowest-order results, the mean field (Hartree-Fock-Bogoliubov equation), and the harmonic potential (quasiparticle random-phase approximation). The method is applied to soft spherical nuclei, where the anharmonicities are essential for restoring the stability of the system, as the harmonic potential becomes small or negative. The approach is tested in three models of increasing complexity: the Lipkin model, model with factorizable forces, and the quadrupole plus pairing model.
  • Modern self-assembly techniques aiming to produce complex structural order or functional diversity often rely on non-equilibrium conditions in the system. Light, electric, or magnetic fields are predominantly used to modify interaction profiles of colloidal particles during self-assembly or induce complex out-of-equilibrium dynamic ordering. The energy injection rate, properties of the environment are important control parameters that influence the outcome of active (dynamic) self-assembly. The current review is focused on a case of collective dynamics and self-assembly of particles with externally driven torques coupled to a liquid or solid interface. The complexity of interactions in such systems is further enriched bymore » strong hydrodynamic coupling between particles. Unconventionally ordered dynamic self-assembled patterns, spontaneous symmetry breaking phenomena, self-propulsion, and collective transport have been reported in torque-driven colloids. Some of the features of the complex collective behavior and dynamic pattern formation in those active systems have been successfully captured in simulations.« less
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  • The electronic multipole response properties of small metal particles are investigated within the frame of a self-consistent spherical jellium model. The method used is the time-dependent local-density approximation (TDLDA), which was used before in a study of the dipole response (W. Ekardt, Phys. Rev. Lett. 52, 1925 (1984)). On comparing the TDLDA response with the response of a system of noninteracting electrons, we see clearly how the electron-electron interaction is switched off rather suddenly around a critical angular momentum l/sup cr/. It is shown that the value of l/sup cr/ can be obtained from the equation q/sup cr/ = l/supmore » cr//R, where R is the radius of the jellium background and q/sup cr/ is the critical wave vector of the planar jellium surface. This result is consistent with a result found earlier for l = 1 (W. Ekardt, Phys. Rev. B 31, 6360 (1985)): A spherical surface behaves across the jellium edge like a patch of a planar jellium surface.« less